半导体激光自混合干涉仪稳定性的仿真分析

利用半导体激光器的Lang-Kobayashi方程,对半导体激光自混合干涉系统的动力学特性进行了仿真分析。研究结果表明,当光反馈系数较小时,激光器处于稳定状态,外腔长度不影响系统的稳定性;当光反馈系数较大时,激光器将进入不稳定状态,对于不同的外腔长度,激光器的稳定状态将发生变化。为实现大量程的位移或距离测量,光反馈系数必须足够小才能保证在较大外腔长度变化范围内,激光器始终处于稳定状态。

Simulation analysis of the stability for self-mixing interferometer with a laser-diode

Using the Lang-Kobayashi equation of the semiconductor lasers,the simulation analysis is given for the dynamic characters of a self-mixing interference system with a laser-diode.It is demonstrated experimentally that semiconductor laser with weak optical feedback,whose external-cavity length hardly makes no influence on the system stability,will be in a state of stability;whereas in case of strong optical feedback,it's state will be in reverse and the capability of that stability will change with the length of external-cavity.To achiever a large range of measurement for displacement or distance,the optical feedback strength should be as little as possible,which make sure the laser in the state of stability within a large changes range of external-cavity length.